The pumps, known as left ventricular assistant devices (LVADs), are employed when the heart's left ventricle is too weak to pump enough blood to nourish the body's tissues. LVADs have been used as successful short-term "bridges to heart transplant" and are increasingly being considered as a long-term heart failure destination therapy, said the researchers from Duke University Medical Center.

In the current trial, the researchers found that patients who received LVADs had an average survival time of 10.3 months, compared to 3.1 months for those who did not receive the device. In this group of end-stage heart failure patients, 78 percent died within six months and 90 percent within a year.

"The patients who received the devices not only had a lengthened quantity of life, but they appeared to have an improved quality of life," said Duke cardiologist Joseph Rogers, M.D. "We had patients who were doing the normal activities of life, such as driving cars, fishing and golfing."

Patients who were on the LVADs scored significantly higher on standard measures of quality of life than patients in the control group, Rogers said.

"This is a remarkably ill group of patients," Rogers continued. "When you look at the control group, which was receiving the best care medicine has to offer, we can only keep ten percent of them alive after one year. We need to focus on this as a group of patients, since most are still in the prime of life and can still be quite productive."

"Despite the shortcomings of the device, the results of this trial speak to our ability to improve the functionality for a very sick group of patients," Rogers said. The major complications of LVADs, said the researchers, include stroke, bleeding episodes and infections, especially at the site in the side of the body where the pump is connected to an external power source and computer.